Here is the full list of all 18 9 Till Void achievements.
Clear The ???
Clear The Grasslands 3 times
Slay a Skeleton Knight
Conquer The Void
Clear The Grasslands
Discover all spells
Win a standard run as The Dreamer
Win a standard run as The Explorer
Win a standard run as The Apprentice
Win a standard run as The Beguiled
Win a standard run as The Cultist
Conquer The Void 9 times
Upgrade Mana per Level and Prepared Spells to their maximum levels in a standard run